What are the indications for aminophylline and deriphylline in pediatric patients?

Indications for Aminophylline and Deriphylline in Pediatric Patients

The primary indication for aminophylline in pediatric patients is as a second-line therapy for acute severe asthma that does not respond to initial treatment with oxygen, corticosteroids, and nebulized bronchodilators. 1

Specific Indications for Aminophylline

Acute Severe Asthma

• Aminophylline is indicated for pediatric patients with further deterioration despite initial treatment with high-flow oxygen, nebulized bronchodilators, and systemic corticosteroids 2
• It should be considered when patients exhibit life-threatening features such as:
  • Cyanosis or silent chest
  • Poor respiratory effort
  • Fatigue or exhaustion
  • Agitation or reduced level of consciousness
  • Peak expiratory flow (PEF) <33% predicted 2, 3

Administration Protocol

• Loading dose: 5 mg/kg administered intravenously over 20 minutes 2
• Maintenance dose: 1 mg/kg/hour as continuous infusion 2
• The loading dose should be omitted if the child is already receiving oral theophyllines 2

Special Considerations

• Due to the immaturity of theophylline metabolic pathways in pediatric patients under one year of age, particular attention to dosage selection and frequent monitoring of serum theophylline concentrations are required 4
• Aminophylline has been shown to improve lung function within 6 hours of treatment when added to standard therapy (beta2-agonists and glucocorticoids) 5
• In African American pediatric patients with status asthmaticus, aminophylline has been associated with lower odds of intubation and mechanical ventilation compared to terbutaline 6

Efficacy and Safety Considerations

Benefits

• Addition of intravenous aminophylline to beta2-agonists and glucocorticoids improves lung function within 6-8 hours of treatment 5
• May reduce the risk of intubation in severe cases 7, 5

Limitations

• Does not significantly reduce symptoms, number of nebulized treatments, or length of hospital stay 5
• Associated with a three-fold increase in the risk of vomiting compared to placebo 5
• No consistent evidence favoring either IV beta2-agonists or IV aminophylline for acute asthma 8

Adverse Effects

• Common adverse effects include nausea and vomiting 5, 8
• Less common but serious adverse effects include arrhythmias and seizures 5

Deriphylline in Pediatrics

• There is insufficient specific evidence in the provided materials regarding the use of deriphylline in pediatric patients
• As deriphylline is a theophylline derivative similar to aminophylline, it would likely have similar indications, but specific guidelines for its use in pediatrics are not provided in the available evidence

Clinical Decision Algorithm

1. First-line treatment for acute asthma in children:

   • High-flow humidified oxygen
   • Nebulized bronchodilators (salbutamol 5 mg or terbutaline 10 mg)
   • Systemic corticosteroids (prednisolone 1-2 mg/kg orally) 2

2. Consider aminophylline when:

   • Patient shows deterioration or inadequate response to first-line treatment
   • Life-threatening features are present 2

3. Contraindications/Cautions:

   • Already receiving oral theophyllines (omit loading dose) 2
   • Age under one year (requires careful dosing and monitoring) 4

4. Monitoring during aminophylline therapy:

   • Vital signs and oxygen saturation
   • Serum theophylline levels if infusion continues beyond 24 hours
   • Observe for adverse effects, particularly vomiting 1, 5

Important Caveats

• Aminophylline should not be used in children at home 2
• The Cochrane review evidence suggests that while aminophylline improves lung function, it does not reduce hospital stay or need for nebulizations 5
• Consider that in some studies, aminophylline may be an alternative to IV beta-agonists when respiratory fatigue begins to develop and ICU admission seems imminent 7